The Philippines sought to assure a panicked public on 15 March that a potential nuclear meltdown in Japan would not affect the country amid fears following widely circulated text messages – dismissed by the country's leading nuclear regulatory agency as a prank – that warned Filipinos to wear raincoats outdoors, hunker down, and stockpile food and medicine because of an imminent radioactive hit.

In the Philippines, an estimated 1bn text messages are sent every day. Some eight out of 10 people had mobile phones in 2009, according to the National Telecommunications Commission.

At least two public schools sent their students home after text messages spread quickly across the country's millions of mobile phone users, with anxious parents and office workers flooding emergency phone lines demanding to know what do in the case of contaminated rain, officials said.

"We have a national radiological emergency preparedness and response plan that was approved as early as 2000. We will put into action this existing plan if there is an emergency," said Philippine Nuclear Research Institute chief Alumanda dela Rosa. "The level of alert at the moment is zero."

She said current wind models indicate that the Philippines, 3,000km southwest of Japan's coast, is not in the direct path of any airborne radioactive material, which is currently blowing eastwards, according to regional monitoring agencies.

But even in a worst-case scenario in Japan, the impact on the Philippines will still be minimal, she said.

Health secretary Enrique Ona said that at the moment there was no need to procure large amounts of iodine to counter possible contamination or quarantine people who transited through Japan.

"Let me be very clear. We don't see the necessity for that. However, we know where we get it if necessary. But we are not going to order it yet," Ona said, adding that the emergency medical personnel were on high alert just in case.

Science and technology secretary Mario Montejo said the public's mass hysteria was "outrageous" and that the government was capable of responding to any emergency related to Japan.

"The university that suspended classes yesterday did not ask us for any recommendation. I don't know how to describe it, except perhaps outrageous and weird that we would even think of suspending classes when in Japan itself classes and office work have resumed," Montejo said.

But for housewife Loida Valenzuela, 40, whose house was swept away by massive flooding that followed tropical storm Ketsana in 2009, extreme preparation is the only way to save lives.

Like Japan, the Philippines sits on the Pacific Ring of Fire, and large parts of its urban areas sit atop fault lines. An estimated 20 typhoons, some of them destructive, batter the country annually, making it among the most disaster-prone places in the world.

"They can call me crazy anytime, but when I got that text yesterday [14 March], I just had to pull out my son from the university," said Valenzuela, whose 18-year-old son is a second-year student at the Polytechnic University of the Philippines that decided to call off classes as a result of the hoax.

"We already lost our house to Ondoy [local name for Ketsana] and I can't take any chances," she said.

Asked whether she does not believe government assurances, she said: "They've made wrong forecasts about typhoons in the past, so we're just being extra careful."